By Tracy Cabrera
BASED on a new study in the United States, children may carry the coronavirus for longer than adults and for longer than previously thought.
After analyzing the medical records of some 60 children who had been tested multiple times for the coronavirus disease or Covid-19, researchers at the Children’s National Hospital found that the median time it took to test negative was from 20 to 25 days.
The study indicated that the median time was longer than some previous estimates and according to a recent study by the National Clinical Research Centre for Infectious Diseases in Shenzhen, China, it was discovered that most children were clear of the virus only after 18 days.
“The takeaway here is that we can’t let our guard down,” said Burak Bahar, lead author of the new stud in a statement.
Among adults, the median time from testing positive to testing negative is around 20 days, according to studies from around the world.
While it is rare for people to be passing on the virus by shedding particles for longer than a month, there have been extreme cases of this happening, such as an asymptomatic patient in southwest China who only tested negative after 45 days.
Bahar’s team found one of the children at the Washington hospital tested positive 62 days after the infection was first confirmed. They noted it was ‘rare’ to conduct serial testing on children—this only happened in about one in 10 cases in the US, according to the medical records examined for the study.
They also said testing positive did not necessarily mean that a child recovering from the virus was still passing it on, since the result could be caused by gene fragments. They said further studies on whether it was possible for the virus to replicate from these fragments were under way.
Tagging them as coronavirus ‘silent spreaders’, they said that children who seem healthy may be more contagious than sick adults.
“Much is still unknown about how the virus affects children, or why they are less likely to get infected and develop severe symptoms than adults,” Bahar pointed out.
The Shenzhen team found that nearly half of the 35 children in their study had no symptoms at all, though some had infections in both lungs and apart from fevers and mild coughs, none of them were in a serious condition.
One theory as to why children appear to be less vulnerable to the virus is that they might have less angiotensin converting enzyme 2 (ACE2), the protein to which the coronavirus binds in order to enter a host cell. Other researchers have suggested that children’s immune response to the virus could differ from that of adults. But there is no scientific evidence as yet to prove either of these differences.